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Investigation of the Bearing Capacity of Transport Constructions Made of Corrugated Metal Structures Reinforced with Transversal Stiffening Ribs

Szabolcs Fischer Vitalii Kovalchuk Mykola Sysyn Majid Movahedi Rad

Publication Name: Infrastructures

Publication Date: 2023-09-01

Volume: 8

Issue: 9

Page Range: Unknown

Description:

Methods of increasing the bearing capacity of corrugated metal structures of transport constructions using transversal stiffening ribs in the form of additional corrugation and stiffeners are given. Based on the theory of elasticity, a mathematical model for estimating the stress-strain state of transport constructions made of corrugated metal structures reinforced with stiffening ribs in the form of double corrugation was developed. The method of determining equivalent forces during rolling stock passage is offered. It has been established that double corrugation increases the bearing capacity of corrugated metal structures. Therefore, additional corrugation of corrugated metal structures reduces stresses by up to 20% and deflections by 50%. The obtained results show that the increase in rolling stock speed does not lead to a significant increase in stresses and strains in CMS when the railway track corresponds to the design state.

Open Access: Yes

DOI: 10.3390/infrastructures8090131

Traffic and Safety Characteristics for the Kurdistan Area: Duhok City

Hamid Athab Al-Jameel Fatimah Fahem Al-Khafaji Ziyad N. Aldoski

Publication Name: Aip Conference Proceedings

Publication Date: 2023-09-01

Volume: 2806

Issue: 1

Page Range: Unknown

Description:

This study focuses mainly on investigating some traffic characteristics according to field observations. The road between Girsheen and Suhela Intersections, in Duhok city, has been examined for some traffic characteristics such as flow, traffic composition, and traffic accidents. Viedo cameras have been adopted to determine the level of service besides using the test car method for identifying the average travel time and speed for the road. Then, the LOS for both directions is relatively low due to insufficient capacity for the traffic volume, which might affect the pavement's service life. On the other hand, the total number of accidents recorded for six months is 73, and fatalities were recorded from 13/3/2020 to 24/9/2020. The percentage of accidents resulting in injuries is 5.48%, and the injury rate is 46 per million vehicle km. The improvement of the injury rate is by 36.98%. This study forecasted an improvement of injury rate by 24.65%.

Open Access: Yes

DOI: 10.1063/5.0162666

Iron Loss Calculation Methods for Numerical Analysis of 3D-Printed Rotating Machines: A Review

Miklós Kuczmann Tamas Orosz Balázs Tóth B. Kocsis Tamás Horváth

Publication Name: Energies

Publication Date: 2023-09-01

Volume: 16

Issue: 18

Page Range: Unknown

Description:

Three-dimensional printing is a promising technology that offers increased freedom to create topologically optimised electrical machine designs with a much smaller layer thickness achievable with the current, laminated steel-sheet-based technology. These composite materials have promising magnetic behaviour, which can be competitive with the current magnetic materials. Accurately calculating the iron losses is challenging due to magnetic steels’ highly nonlinear hysteretic behaviour. Many numerical methodologies have been developed and applied in FEM-based simulations from the first introduced Steinmetz formulae. However, these old curve-fitting-based iron loss models are still actively used in modern finite-element solvers due to their simplicity and high computational demand for more-accurate mathematical methods, such as Preisach- or Jiles–Atherton-model-based calculations. In the case of 3D-printed electrical machines, where the printed material can have a strongly anisotropic behaviour and it is hard to define a standardised measurement, the applicability of the curve-fitting-based iron loss methodologies is limited. The following paper proposes an overview of the current problems and solutions for iron loss calculation and measurement methodologies and discusses their applicability in designing and optimising 3D-printed electrical machines.

Open Access: Yes

DOI: 10.3390/en16186547

A Hybrid Discrete Memetic Algorithm for Solving Flow-Shop Scheduling Problems

Olivér Hornyák Károly Nehéz Boldizsar Tuu-Szabo Levente Fazekas Ĺaszĺo T. Ḱoczy

Publication Name: Algorithms

Publication Date: 2023-09-01

Volume: 16

Issue: 9

Page Range: Unknown

Description:

Flow-shop scheduling problems are classic examples of multi-resource and multi-operation scheduling problems where the objective is to minimize the makespan. Because of the high complexity and intractability of the problem, apart from some exceptional cases, there are no explicit algorithms for finding the optimal permutation in multi-machine environments. Therefore, different heuristic approaches, including evolutionary and memetic algorithms, are used to obtain the solution—or at least, a close enough approximation of the optimum. This paper proposes a novel approach: a novel combination of two rather efficient such heuristics, the discrete bacterial memetic evolutionary algorithm (DBMEA) proposed earlier by our group, and a conveniently modified heuristics, the Monte Carlo tree method. By their nested combination a new algorithm was obtained: the hybrid discrete bacterial memetic evolutionary algorithm (HDBMEA), which was extensively tested on the Taillard benchmark data set. Our results have been compared against all important other approaches published in the literature, and we found that this novel compound method produces good results overall and, in some cases, even better approximations of the optimum than any of the so far proposed solutions.

Open Access: Yes

DOI: 10.3390/a16090406

Oil Degradation Patterns in Diesel and Petrol Engines Observed in the Field—An Approach Applying Mass Spectrometry

Charlotte Besser Péter Raffai Marcella Frauscher András Lajos Nagy Adam Agocs Andjelka Ristic Zsolt Tabakov

Publication Name: Lubricants

Publication Date: 2023-09-01

Volume: 11

Issue: 9

Page Range: Unknown

Description:

Engine oil degradation and tribological properties are strongly interrelated. Hence, understanding the chemical processes resulting in additive depletion and degradation products is necessary. In this study, in-service engine oils from petrol and diesel vehicles were analyzed with conventional and advanced methods (mass spectrometry). Additionally, the effect of the utilization profile (short- vs. long-range) was studied. Petrol engine oils generally showed accelerated antioxidant and antiwear degradation and higher oxidation, especially in the case of a short-range utilization profile, which can be attributed to the higher air-to-fuel ratio (more rich combustion) compared to diesel engines. A detailed overview of oxidation and nitration products, as well as degradation products resulting from zinc dialkyl dithiophosphate and boron ester antiwear additives, diphenylamine antioxidants and salicylate detergents is given. A side reaction between oxidation products (aromatic carboxylic acids) and the boron ester antiwear is highlighted. This reaction was only detected in the petrol engine oils, where the oxidation products were measured in a high abundance. However, no side reaction was found in the samples from the diesel vehicles, since there the aromatic carboxylic acids were largely absent due to lower oxidation.

Open Access: Yes

DOI: 10.3390/lubricants11090404

Effective lane width analysis for autonomous trucks

Richárd Nagy Mohammad Fahad

Publication Name: SN Applied Sciences

Publication Date: 2023-09-01

Volume: 5

Issue: 9

Page Range: Unknown

Description:

Lateral wander of autonomous truck can be further improved by optimizing the uniform wander. Increase in available lane width for the autonomous trucks can increase the performance efficiency of this mode. This research is based on finding the optimum, combination of lane width increment and asphalt layer thickness reduction among different scenarios. Therefore, In this research with assumed maximum lane width of 4.35 m, difference combination of lane width and asphalt layer thickness scenarios have been analyzed using finite element modelling in ABAQUS. Considering the base pavement width of 3.75 m, increment for each scenario is 15 cm and reduction in asphalt layer thickness is at 2 cm. Performance efficiency of each scenario is conducted while considering the initial construction costs and damage assessment for each scenario. Moreover, life cycle cost analysis (LCCA) is conducted for the base scenario and selected optimum scenario. Results show that increase in pavement width beyond 4.2 m, renders the scenarios uneconomical and thus, the scenario consisting of 4.2 m lane width and 16 cm asphalt layer thickness yield a maximum performance efficiency of 20% among all other alternatives. LCCA analysis shows that a difference in salvage value of 42 million Euros exists when compared with the base scenario. By selecting the optimum lane width of 4.2 m and asphalt layer thickness of 16 cm, Pavement lifetime can be further increased by 13 years with full depth reclamation used as maintenance intervention.

Open Access: Yes

DOI: 10.1007/s42452-023-05446-0

Optimization of vertical farms energy efficiency via multiperiodic graph-theoretical approach

Jean Pimentel Ferenc Friedler L. Balázs

Publication Name: Journal of Cleaner Production

Publication Date: 2023-09-01

Volume: 416

Issue: Unknown

Page Range: Unknown

Description:

A systematic method is proposed for enhancing the energy efficiency of vertical farms when integrated into urban infrastructure. The method relies on the optimization of a multiperiod model that determines the system's best operation plan considering variations in its parameters throughout the day. These parameters include factors such as resources availability from the urban infrastructure and fluctuations in electricity prices. The model is formulated and solved via the tools of the P-graph framework, which permits the automatic formulation of the rigorous superstructure and the efficient optimization of the integrated system's operation. The method is illustrated via a case study comprising three scenarios. The most efficient case demonstrates up to 40% electricity cost saving potential for a particular operation day, and up to 31% for the entire year. The method presented constitutes an optimization tool that can use real data on electricity prices and forecasts of weather conditions to reduce operating costs and enhance the energy efficiency and sustainability of vertical farming systems.

Open Access: Yes

DOI: 10.1016/j.jclepro.2023.137938

Increasing the functionality of sponge cakes by mint, and cocoa powder addition

E. Lakatos V. Kapcsándi Székelyhidi Rita Beatrix Sik Krisztina Kovács

Publication Name: Heliyon

Publication Date: 2023-09-01

Volume: 9

Issue: 9

Page Range: Unknown

Description:

While sponge cake is one of the most well-liked cookies in the world, mint and cocoa have both been shown to be excellent sources of antioxidant compounds. Therefore, the aim of the study was to create functional sponge cakes with the addition of Dutch cocoa powder and different types of mint, with proven increased total antioxidant and polyphenol content. Additionally, made an effort to produce functional sponge cakes enhanced with cocoa powder and dried, ground mint leaves. To accomplish this, the cakes with cocoa addition were also added 1, 3, and 5% of the ground mint variety, and then the changes in their antioxidant and polyphenol content were assessed. To prove the functionality of cakes, total polyphenol content was detected by Folin-Ciocalteu, while all antioxidant content was measured by the FRAP method. The spectrophotometric analysis supported the functionality of sponge cakes and the baking losses of identified components. The total polyphenol content of baked goods ranged from 1.37 to 1.66 mg GAE/g for peppermint cakes, from 1.66 to 1.87 mg GAE/g for spearmint cakes, and from 1.20 to 1.68 mg GAE/g for strawberry mint sponge cakes. The total antioxidant content of the functional cakes changed between 1.84 and 2.82 mg AAE/g for peppermint cakes, from 1.84 to 4.00 mg AAE/g for spearmint cakes, and from 1.56 to 2.94 mg GAE/g for strawberry mint sponge cakes. The natural control samples, and control sponge cakes made without mint addition with only cocoa powder always had lower levels of polyphenols and antioxidants. All samples had baking loss (control samples had the highest in all cases), but strawberry mint samples had the least of it when it came to antioxidant content and spearmint samples had the least in the case of polyphenol content. Overall, mints and Dutch cocoa powder are appropriate for the production of functional bakery goods because they give the final product a tasty flavor and provide a significant amount of antioxidants and polyphenols despite baking.

Open Access: Yes

DOI: 10.1016/j.heliyon.2023.e20029

Development of the financial situation of Hungarian food industry enterprises - changes between 2017 and 2021

Károly Kacz Szabolcs Troján Judit Hegyi Anita Miklósné Varga

Publication Name: Economic and Regional Studies Studia Ekonomiczne I Regionalne

Publication Date: 2023-09-01

Volume: 16

Issue: 3

Page Range: 348-366

Description:

Subject and purpose of work:: The aim of the study is to analyse how the main financial data of d ouble-entry b ookkeeping f ood p rocessing e nterprises r eflect t he e ffects o f t he i ndicated economic environment. Materials and methods:: The evaluation was fundamentally based on ratios calculated on the basis of the statement of financial position and the income statement as well as trend analysis and financial indicators. Results:: The number of Hungarian food processing enterprises has been gradually decreasing over the period under review. Both turnover and expenditure show linear growth at current prices, with increases in the various result categories. The asset structure is stable, and profitability is improving. Conclusions:: The number of companies and the employment in the sector have been steadily declining in recent years, while efficiency is increasing. The increase in profits in the food industry is remarkable for all branches of the economy. The sector is adapting well to the negative effects of the changing economic environment.

Open Access: Yes

DOI: 10.2478/ers-2023-0022